Operation and maintenance manual

Inspection, Maintenance and Adjustment
4-79
DX140R/DX140LCR
TRACK TENSION
NOTE: The track tension must be adjusted in accordance
with the operating conditions. If a lot of dust stick to
the track assembly in the working place, keep the
track as loose as possible.
Track shoe link pins and bushings wear with normal usage,
reducing
track tension. Periodic adjustment is necessary to
compensate for wear and it may also be required by working
conditions.
1. Track tension is checked by jacking up one side of the
excavator. See Figure 127. Place blocking under frame
while taking measurement.
Turn the track backward 1 ~ 2 turns.
2. Measuring the distance (A, Figure 128) between the
bottom of the side frame and the top of the lowest crawler
shoe
. Recommended tension for operation over most
types of terrain is as below table.
NOTE: Clea
n off the tracks before checking clearance
for accurate measurements.
3. Too little sag in the crawler track (less than clearance
distan
ce "A" on below table) can cause excessive
component wear. The recommended adjustment can also
be too tight causing accelerated stress and wear if ground
conditions are wet, marshy or muddy.
WARNING
AVOID DEATH OR SERIOUS INJURY
Measuring track tension requires two people. One person
must be
in the operator's seat, operating the controls while
the other person makes dimensional checks. Block frame to
make sure the machine won't move or shift position during
service. Warm up the engine to prevent stalls, park the
excavator in an area that provides level, uniform ground
support and/or use support blocks when necessary.
EX1300536
90 ~ 110
Figure 127
A
FG000162
Figure 128